Lots of us depend on Microsoft's venerable Outlook for e-mail and contacts. And after all these years, there's still plenty of ways it can improve. Just try to dig up an old e-mail with Outlook's primitive search tool. At least Microsoft has encouraged a cottage industry for third-party Outlook add-ons that can help. I've been testing two handy ones Gwabbit from Technicopia in Carmel Valley, Calif., and Xobni from a San Francisco start-up of the same name.